That's a very important distinction.
An anchor is a goal you have that's guiding the overall fiscal decisions: spending, taxing and so on. A guardrail, rather—at least as described by the government—is something that will determine when you stop some types of expenditures. In that case, the guardrails have been expressed, at least so far, as the labour market indicators: the unemployment rate, the number of hours worked and the participation rate, if I'm not mistaken. One is shorter term. The other is longer term.